Transmission loss and noise reduction of reactive mufflers are determined by linear acoustic theory and unsteady flow field study, respectively. The effects of extending the inlet tube of the muffler, adding holes to the extension, and the number of holes on both transmission loss and noise reduction are investigated. In noise reduction analysis, the Navier-Stokes equations and k-ε model are us...

using a new numerical model, the pump-to-signal relative intensity noise (rin) transfer in singlepumpfiber optical parametric amplifiers for low modulation frequencies is investigated. the model includesfiber loss, pump depletion, as well as the gain saturation, and therefore, it can describe the practicalcircumstances associated with various applications of fiber optical parametric amplifiers....

We introduce a new principle for model selection in regression and classification. Many regression models are controlled by some smoothness or flexibility or complexity parameter c, e.g. the number of neighbors to be averaged over in k nearest neighbor (kNN) regression or the polynomial degree in regression with polynomials. Let f̂ c D be the (best) regressor of complexity c on data D. A more fl...

A key issue in statistics and machine learning is to automatically select the “right” model complexity, e.g., the number of neighbors to be averaged over in k nearest neighbor (kNN) regression or the polynomial degree in regression with polynomials. We suggest a novel principle the Loss Rank Principle (LoRP) for model selection in regression and classification. It is based on the loss rank, whi...

This paper describes an improved model for multiple building diffraction modeling based on the uniform theory of diffraction (UTD). A well-known problem in conventional uniform theory of diffraction (CUTD) is multiple-edge transition zone diffraction. Here, higher order diffracted fields are used in order to improve the result; hence, we use higher order diffraction coefficients to improve a hy...

background: relapse is a common problem in drug user’s rehabilitation program and reported in all over the country. an in-depth study on patients’ experiences can be used for exploring the relapse process among drug users. therefore, this study suggests a model for relapse process among iranian drug users. methods: in this qualitative study with grounded theory approach, 22 participants with ri...